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Is there PFAS in City of Clovis water?

Yes. EPA's final UCMR 5 results show City of Clovis averaged 36.0 ppt of PFOS at its worst sampling point, 9.0 times the EPA limit of 4 ppt.

City of Clovis Serves 130,130 people · 78 PFOA samples from 38 sampling points · Feb 2023 to May 2024 Average above an EPA limit
PFOA Perfluorooctanoic acid 16.0 ppt avg · max 18.0
EPA 4
PFOS Perfluorooctanesulfonic acid 36.0 ppt avg · max 41.0
EPA 4
PFHxS Perfluorohexanesulfonic acid 6.6 ppt avg · max 8.8
EPA 10
PFNA Perfluorononanoic acid 6.1 ppt avg · max 6.9
EPA 10
Hazard index GenX, PFBS, PFNA, PFHxS combined 1.3 avg
EPA 1

Also detected, no federal limit: PFPeA, PFHxA, PFBS, PFBA, PFHpA, PFDA.

Averages are for the worst sampling point, with non-detects counted as zero. Source: EPA UCMR 5.

City of Clovis is a public water system drawing on surface water, based in Clovis, California, serving about 130,130 people, including Clovis, Fresno. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 78 times across 38 sampling points between Feb 2023 and May 2024.

Every PFAS detected

PFAS Detected Highest Worst point avg EPA limit
PFOS
Perfluorooctanesulfonic acid
8 of 78 41.0 ppt 36.0 ppt 4 ppt
PFOA
Perfluorooctanoic acid
9 of 78 18.0 ppt 16.0 ppt 4 ppt
PFHxS
Perfluorohexanesulfonic acid
4 of 78 8.8 ppt 6.6 ppt 10 ppt
PFPeA
Perfluoropentanoic acid
3 of 78 8.4 ppt 7.8 ppt none
PFHxA
Perfluorohexanoic acid
6 of 78 8.0 ppt 7.5 ppt none
PFBS
Perfluorobutanesulfonic acid
10 of 78 7.9 ppt 7.7 ppt none
PFNA
Perfluorononanoic acid
2 of 78 6.9 ppt 6.1 ppt 10 ppt
PFBA
Perfluorobutanoic acid
1 of 78 6.1 ppt 3.1 ppt none
PFHpA
Perfluoroheptanoic acid
2 of 78 5.7 ppt 5.2 ppt none
PFDA
Perfluorodecanoic acid
2 of 78 3.1 ppt 3.0 ppt none

Not detected: PFPeS, HFPO-DA, 6:2 FTS, 4:2 FTS, 8:2 FTS, PFMPA, PFMBA, NFDHA, 9Cl-PF3ONS, PFHpS, ADONA, PFEESA, 11Cl-PF3OUdS, PFTrDA, NMeFOSAA, PFTA, PFDoA, PFUnA, NEtFOSAA.

Lithium, tested in the same program: not detected.

What the EPA limits mean here

In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.

Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.

What you can do at home

Two routes work for PFAS. For drinking and cooking water only, a reverse osmosis system certified to NSF/ANSI 58 with a PFOA/PFOS reduction claim is the cheapest proven option. To treat every tap and shower, a whole-house carbon system with enough contact time works, but check that the maker has PFAS test data, not just a marketing claim. See the best filters for PFAS and how PFAS removal works.

Other systems in California

All 707 tested systems in California

ZIP codes served

93611 93612 93619 93727

As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.

Cite this page

Well & Tap. "PFAS in City of Clovis water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID CA1010003. https://wellandtap.com/pfas/california/city-of-clovis/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID CA1010003). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.